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(#) Separate attach() and detach() into separate FragmentTransactions

!!! WARNING: Separate attach() and detach() into separate FragmentTransactions
   This is a warning.

Id
:   `DetachAndAttachSameFragment`
Summary
:   Separate attach() and detach() into separate FragmentTransactions
Severity
:   Warning
Category
:   Correctness
Platform
:   Android
Vendor
:   Android Open Source Project
Identifier
:   androidx.fragment
Feedback
:   https://issuetracker.google.com/issues/new?component=460964
Min
:   Lint 7.0
Compiled
:   Lint 8.0 and 8.1
Artifact
:   [androidx.fragment:fragment](androidx_fragment_fragment.md.html)
Since
:   1.4.0
Affects
:   Kotlin and Java files
Editing
:   This check runs on the fly in the IDE editor
Implementation
:   [Source Code](https://cs.android.com/androidx/platform/frameworks/support/+/androidx-main:/fragment/fragment-lint/src/main/java/androidx/fragment/lint/AttachAndDetachInSameTransactionDetector.kt)
Tests
:   [Source Code](https://cs.android.com/androidx/platform/frameworks/support/+/androidx-main:/fragment/fragment-lint/src/test/java/androidx/fragment/lint/AttachAndDetachInSameTransactionDetectorTest.kt)
Copyright Year
:   2019

When doing a FragmentTransaction that includes both attach()
    and detach() operations being committed on the same fragment
instance, it is a                 no-op. The reason for this is that the
FragmentManager optimizes all operations                 within a single
transaction so the attach() and detach() cancel each other out
      and neither is actually executed. To get the desired behavior, you
should separate                 the attach() and detach() calls into
separate FragmentTransactions.

(##) Including

!!!
   This is not a built-in check. To include it, add the below dependency
   to your project.

```
// build.gradle.kts
implementation("androidx.fragment:fragment:1.8.5")

// build.gradle
implementation 'androidx.fragment:fragment:1.8.5'

// build.gradle.kts with version catalogs:
implementation(libs.fragment)

# libs.versions.toml
[versions]
fragment = "1.8.5"
[libraries]
# For clarity and text wrapping purposes the following declaration is
# shown split up across lines, but in TOML it needs to be on a single
# line (see https://github.com/toml-lang/toml/issues/516) so adjust
# when pasting into libs.versions.toml:
fragment = {
    module = "androidx.fragment:fragment",
    version.ref = "fragment"
}
```

1.8.5 is the version this documentation was generated from;
there may be newer versions available.

[Additional details about androidx.fragment:fragment](androidx_fragment_fragment.md.html).
(##) Suppressing

You can suppress false positives using one of the following mechanisms:

* Using a suppression annotation like this on the enclosing
  element:

  ```kt
  // Kotlin
  @Suppress("DetachAndAttachSameFragment")
  fun method() {
     beginTransaction(...)
  }
  ```

  or

  ```java
  // Java
  @SuppressWarnings("DetachAndAttachSameFragment")
  void method() {
     beginTransaction(...);
  }
  ```

* Using a suppression comment like this on the line above:

  ```kt
  //noinspection DetachAndAttachSameFragment
  problematicStatement()
  ```

* Using a special `lint.xml` file in the source tree which turns off
  the check in that folder and any sub folder. A simple file might look
  like this:
  ```xml
  &lt;?xml version="1.0" encoding="UTF-8"?&gt;
  &lt;lint&gt;
      &lt;issue id="DetachAndAttachSameFragment" severity="ignore" /&gt;
  &lt;/lint&gt;
  ```
  Instead of `ignore` you can also change the severity here, for
  example from `error` to `warning`. You can find additional
  documentation on how to filter issues by path, regular expression and
  so on
  [here](https://googlesamples.github.io/android-custom-lint-rules/usage/lintxml.md.html).

* In Gradle projects, using the DSL syntax to configure lint. For
  example, you can use something like
  ```gradle
  lintOptions {
      disable 'DetachAndAttachSameFragment'
  }
  ```
  In Android projects this should be nested inside an `android { }`
  block.

* For manual invocations of `lint`, using the `--ignore` flag:
  ```
  $ lint --ignore DetachAndAttachSameFragment ...`
  ```

* Last, but not least, using baselines, as discussed
  [here](https://googlesamples.github.io/android-custom-lint-rules/usage/baselines.md.html).

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